Abstract: An encryption approach based on cross-coupling chaotic system is proposed.In this algorithm，a new logistic model of cross-coupling is defined.This cross-coupling chaotic system can produce two groups of sequences at the same time.One is used to shuffle the images，and the other to encrypt the image information by changing the grey values of the pixels.The difference between this algorithm and the present one lies in the fact that the former uses one chaotic system to shuffle and encrypt at the same time while the latter uses two separate chaotic systems to shuffle and encrypt respectively.Simulation results and security analysis show that this improved algorithm，which can widen the key space，is of greater security and of less time complexity.

摘要： 提出了一种基于交叉耦合的“新虫口模型”的图像加密算法。利用这种交叉耦合混沌系统同时生成两组混沌序列，并用其中一组来置乱图像，另外一组改变像素灰度值进行加密。这种使用单一耦合混沌系统同时置乱和加密的算法，有别于目前用一个混沌系统置乱、用另一个混沌系统加密图像的主流算法，提出了一种改进的混沌加密图像思路。仿真结果和安全分析表明该算法扩大了密钥空间，具有较高的安全性能和较低的时间复杂度。